边坡岩体结构的三维失稳形式及稳定性分析研究

由两组结构面控制的四面体块体是岩体中最基本的结构体, 其稳定性取决于块体所受荷载及结构面上的摩阻力。正确判定边界面上摩阻力分布是评价块体稳定性的关键。本文提出的块体稳定性分析适用于岩体所受荷载为三维非共点力系。在不同外力作用下块体可产生平动、转动、翘扭及倾倒等各种三维失稳组合形式, 从而得到更为合理的块体稳定性评价。

ON THE 3 D UNSTABLE ROCKS AND STABILITY ANALYSIS OF SLOPE ROCKMASS STRUCTURE

The problem presented in this paper is a stability analysis of rock block, separated by a set of two geologic structural surfaces from slope rockmass and loaded by a 3 D force system without common point of force action. The method developed in this paper is based upon the use of vector analysis, the principle of nodal equivalent forces, and that the distribution of friction force at any point on a geologic structural surface is treated as a function of the normal pressure acted on that point on the surface and the relative displacement of the block at that point along the surface. Thus the block movement may involve not only parallel translation, but also sliding rotation and other 3 D movement. Finally, a computer program is proposed to solve the stability of rock block for various possible modes of its instability.